We entered 5 patients in the hypertrophy-pacing study over the past year. All patients have completed their initial 6 month follow-up, therefore data from a randomized period of 3 months pacing off versus 3 months pacing on are already available. Our results are very encouraging, in that there is already a significant improvement in exercise capacity, measured both by exercise time and maximal oxygen consumption. The echocardiographic changes are less clear as yet, although there are reductions in chamber wall thickness in several patients. We recently entered patient 6 into the protocol, and hope to complete the study (total of 10 patients) by the third month of 1997. All of the patients studied to date are continuing in the protocol, they have entered the 6 month period of pacing-on, and we will have 1 year follow-up data available by later this summer. None of these patients is reporting a worsening of symptoms, and several have experienced marked improvements. There have been no complications to date.